This invention relates to cannulae.
The invention is more particularly concerned with operative cholangiogram or similar cannulae.
Operative cholangiogram cannulae are used to introduce an X-ray opaque fluid into the common bile duct following removal of the gall bladder (cholecystectomy). This makes it possible to check, by X-ray observation, whether any small stones remain in the bile duct.
These cannulae are made of a plastics material, such as polyethylene, and are of a relatively small external diameter, typically about 1.4 mm. They are introduced into the bile duct using forceps to grip the end of the cannula.
One problem that arises with such cannulae is that they are easily crushed or kinked during introduction.